1 files changed, 86 insertions, 0 deletions
diff --git a/src/corelib/global/qversiontagging.h b/src/corelib/global/qversiontagging.h
new file mode 100644
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+++ b/src/corelib/global/qversiontagging.h
@@ -0,0 +1,86 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Intel Corporation.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** As a special exception, The Qt Company gives you certain additional
+** rights. These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// qglobal.h includes this header, so keep it outside of our include guards
+#include <QtCore/qglobal.h>
+
+#if !defined(QVERSIONTAGGING_H)
+#define QVERSIONTAGGING_H
+
+QT_BEGIN_NAMESPACE
+
+/*
+ * Ugly hack warning and explanation:
+ *
+ * This file causes all ELF modules, be they libraries or applications, to use the
+ * qt_version_tag symbol that is present in QtCore. Such symbol is versioned,
+ * so the linker will automatically pull the current Qt version and add it to
+ * the ELF header of the library/application. The assembly produces one section
+ * called ".qtversion" containing two pointer-sized values. The first is a
+ * relocation to the qt_version_tag symbol (which is what causes the ELF
+ * version to get used). The second value is the current Qt version at the time
+ * of compilation.
+ *
+ * There will only be one copy of the section in the output library or application.
+ */
+
+#if defined(QT_BUILD_CORE_LIB) || defined(QT_BOOTSTRAPPED) || defined(QT_NO_VERSION_TAGGING)
+// don't make tags in QtCore, bootstrapped systems or if the user asked not to
+#elif defined(Q_CC_GNU)
+#  if defined(Q_PROCESSOR_X86) && (defined(Q_OS_LINUX) || defined(Q_OS_FREEBSD_KERNEL))
+#    ifdef __LP64__
+#      define QT_VERSION_TAG_RELOC(sym) ".quad " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) "@GOTPCREL\n"
+#    elif defined(Q_PROCESSOR_X86_64)   // x32
+#      define QT_VERSION_TAG_RELOC(sym) ".long " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) "@GOTPCREL\n"
+#    else                               // x86
+#      define QT_VERSION_TAG_RELOC(sym) ".long " QT_STRINGIFY(QT_MANGLE_NAMESPACE(sym)) "@GOT\n"
+#    endif
+#    define QT_VERSION_TAG(sym) \
+    asm (   \
+    ".section .qtversion, \"aG\", @progbits, qt_version_tag, comdat\n" \
+    ".align 8\n" \
+    QT_VERSION_TAG_RELOC(sym) \
+    ".long " QT_STRINGIFY(QT_VERSION) "\n" \
+    ".align 8\n" \
+    ".previous" \
+    )
+#  endif
+#endif
+
+#if defined(QT_VERSION_TAG)
+QT_VERSION_TAG(qt_version_tag);
+#endif
+
+QT_END_NAMESPACE
+
+#endif // QVERSIONTAGGING_H